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2. Radiometric and photometric quantities
2.1 Flow
Flux Φ is the instantaneous value of a radiation flow. It may be all the radiation emitted by a source, or only that carried by the beam leaving an instrument, or even that received by a detector.
Flux can be measured by the power (in watts: system of energy units) it carries, or by the number of photons it delivers per unit of time (in s –1 : system of photon units).
SCROLL TO TOP2.2 Geometric extent
Consider a source surface S illuminating...
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Radiometric and photometric quantities
Bibliography
References
Standardization
Association française de normalisation AFNOR
- Vocabulaire électronique. Chapitre 845 : Éclairage º [CEI 50 (845)]. - NF C 01-845 - 3-89
Manufacturers. Suppliers
Manufacturers
Standard sources for radiometry: 18, 19, 20
Standard sources for photometry: 18, 19, 20
Detectors for radiometry: thermal: 5, 12, 13, 17
Detectors for radiometry: photoelectric: 2, 4, 6, 7, 27
Photometric detectors: 19
Radiometers (flux, irradiance):...
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